Where can I find a big Flying saucer

Hello!

I already got a 16 inch wheel and 2 of my 4 chinchilla’s love it!

But for the other 2 I was looking for a big (14inch or bigger) safe Flying saucer. But I can’t find one that is safe (metal) and big enough for them. A wooden one will me distroyed in a vew days.

Can you help me?